1. Field of the Invention
The present invention relates to a semiconductor laser. More particularly, the invention relates to a semiconductor laser with a lateral optical cavity based on III-V and II-VI semiconductor compounds and their alloys.
2. Description of the Prior Art
Semiconductor laser diodes with various shapes of lateral laser cavities such as micro-disk, equilateral triangle, micro-arc-ring, triangular ridge, L-shape ridge, U-shape ridge and bow-tie lasers are known, e.g. CN1267106.
In all these lasers surface mesa structures of various shapes are used for lateral light confinement.
However, the light reflections at the sides of mesa structures are not wavelength sensitive. These makes the surface mesa-structure-based optical resonators non-selective with respect to the different lateral optical modes and prevents fabrication of semiconductor lasers operating in a single mode or controlled multiple mode regimes.
Meanwhile, many applications require single mode or controllable multiple mode operation of semiconductor laser.
The present invention states semiconductor lasers with polygonal surface optical grating resonator (PGR) for lateral confinement of the light which allows selective excitation of the chosen optical mode or modes needed for various applications such as CD and DVD pick up heads, high quality laser printers and others.
Also, PGR allows controlled multiple wavelength operation of semiconductor lasers needed for telecommunication purposes.
It is an object of the present invention to provide a semiconductor laser which can operate in single mode or controllable multiple mode regimes.